KR20200110906A - Electronic device for auto focusing function and operating method thereof - Google Patents

Abstract

Various embodiments of the present invention are to provide an electronic device for performing auto focusing without shaking of an image in the electronic device, and an operating method thereof. According to an embodiment, an electronic device comprises a camera module including a focus lens, a display, and a processor. The processor is configured to control the camera module to obtain a first image at a first position of the focus lens, and control the display to output the first image. The processor is also configured to control the camera module to obtain a second image at a second position of the focus lens while the first image is being output, calculate a defocus amount of the focus lens at the second position based on the first image and the second image, and detect an on-focus region on the basis of the calculated defocus amount.

Description

Electronic device for providing auto focus control function and its operation method {ELECTRONIC DEVICE FOR AUTO FOCUSING FUNCTION AND OPERATING METHOD THEREOF}

Various embodiments of the present invention relate to an electronic device for providing an automatic focus adjustment function, and more particularly, to an electronic device for removing a wobbling phenomenon that occurs while performing an automatic focus adjustment function, and an operating method thereof. will be.

In recent years, digital cameras, digital camcorders, and electronic devices equipped with cameras, such as smart phones, have been actively spreading. An electronic device equipped with such a camera may provide a photographing function. For example, the electronic device may output a preview screen on a display using an image acquired in real time from a camera and obtain a captured image from the camera when a capturing input is received.

In addition, the electronic device provides an auto focus function that automatically focuses on a subject.

In general, the auto focus function is a function that focuses on a subject by moving the lens included in the camera back and forth, and the electronic device displays an image received through the camera while the auto focus function is being executed. It can be output as a preview image or live view. However, there is a problem that the field of view of the image output to the display device is frequently shaken (e.g., wobbling) due to frequent movement of the focus lens during the auto focus function. .

Accordingly, various embodiments of the present disclosure are directed to providing an electronic device and a method of operating the same for performing autofocus without causing image shaking in an electronic device.

The technical problems to be achieved in this document are not limited to the technical problems mentioned above, and other technical problems that are not mentioned can be clearly understood by those of ordinary skill in the technical field to which the present invention belongs from the following description. There will be.

An electronic device according to various embodiments of the present disclosure includes a camera module including a focus lens, a display device, and a processor, wherein the processor includes the camera module to acquire a first image at a first position of the focus lens. Control, control the display device to output the first image, control the camera module to acquire a second image at a second position of the focus lens while the first image is output, and the first Based on the image and the second image, a defocus amount for the focus lens at the second position may be calculated, and the on-focus area may be detected based on the calculated defocus amount.

An operation method of an electronic device according to various embodiments of the present disclosure includes an operation of acquiring a first image at a first position of a focus lens, an operation of outputting the first image through a display device, and an operation of outputting the first image. During the operation, an operation of acquiring a second image at a second position of the focus lens, an operation of calculating a defocus amount for the focus lens at the second position based on the first image and the second image, and the calculation It may include an operation of detecting an on-focus area based on the defocused amount.

The computer-readable recording medium according to various embodiments of the present disclosure includes an operation of acquiring a first image at a first position of a focus lens, an operation of outputting the first image through a display device, and an operation of outputting the first image. , An operation of acquiring a second image at a second position of the focus lens, an operation of calculating a defocus amount for the focus lens at the second position based on the first image and the second image, and the calculated A program for executing an operation of detecting an on-focus area based on the amount of defocus can be stored.

The electronic device according to various embodiments of the present disclosure may provide an effect of preventing image wobbling from occurring by outputting an image initially acquired until a search position is determined by an initial operation of an auto focus function.

The effects obtainable in the present invention are not limited to the above-mentioned effects, and other effects not mentioned can be clearly understood by those of ordinary skill in the technical field to which the present invention belongs from the following description. will be.

1 is a block diagram of an electronic device in a network environment, according to various embodiments.
2 is a block diagram illustrating a camera module, according to various embodiments.
3 is a diagram illustrating an auto focus operation of an electronic device according to various embodiments of the present disclosure.
4 is a flowchart for providing an auto focus function in an electronic device according to various embodiments of the present disclosure.
5A is an exemplary diagram for describing an auto focus function of a general electronic device.
5B is an exemplary diagram illustrating an auto focus function of an electronic device according to various embodiments of the present disclosure.
6 is a flowchart for calculating a defocus amount in an electronic device according to various embodiments of the present disclosure.
7 is a flowchart for detecting an on focus area in an electronic device according to various embodiments of the present disclosure.
8 is an exemplary diagram for describing an operation of detecting an on focus area in an electronic device according to various embodiments of the present disclosure.
9 is a flowchart for moving a focus lens based on a search position in an electronic device according to various embodiments of the present disclosure.
10A to 10C are exemplary diagrams for explaining an operation of moving a focus lens based on a search position in an electronic device according to various embodiments of the present disclosure.
11 is a flowchart for updating a screen based on a second image in an electronic device according to various embodiments of the present disclosure.
In connection with the description of the drawings, the same or similar reference numerals may be used for the same or similar components.

Hereinafter, various embodiments of the present invention will be described in detail with reference to the accompanying drawings. In addition, in describing an embodiment of the present invention, when it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, a detailed description thereof will be omitted. In addition, terms to be described later are terms defined in consideration of the functions of the present invention, which may vary according to the intention or custom of users or operators. Therefore, the definition should be made based on the contents throughout this specification.

1 is a block diagram of an electronic device 101 in a network environment 100 according to various embodiments. Referring to FIG. 1, in a network environment 100, the electronic device 101 communicates with the electronic device 102 through a first network 198 (for example, a short-range wireless communication network), or a second network 199 It is possible to communicate with the electronic device 104 or the server 108 through (eg, a long-distance wireless communication network). According to an embodiment, the electronic device 101 may communicate with the electronic device 104 through the server 108. According to an embodiment, the electronic device 101 includes a processor 120, a memory 130, an input device 150, an audio output device 155, a display device 160, an audio module 170, and a sensor module ( 176, interface 177, haptic module 179, camera module 180, power management module 188, battery 189, communication module 190, subscriber identification module 196, or antenna module 197 ) Can be included. In some embodiments, at least one of these components (eg, the display device 160 or the camera module 180) may be omitted or one or more other components may be added to the electronic device 101. In some embodiments, some of these components may be implemented as one integrated circuit. For example, the sensor module 176 (eg, a fingerprint sensor, an iris sensor, or an illuminance sensor) may be implemented while being embedded in the display device 160 (eg, a display).

The processor 120, for example, executes software (eg, a program 140) to implement at least one other component (eg, a hardware or software component) of the electronic device 101 connected to the processor 120. It can be controlled and can perform various data processing or operations. According to an embodiment, as at least a part of data processing or operation, the processor 120 stores commands or data received from other components (for example, the sensor module 176 or the communication module 190), and The command or data stored in the volatile memory 132 may be processed, and result data may be stored in the nonvolatile memory 134. According to an embodiment, the processor 120 includes a main processor 121 (eg, a central processing unit or an application processor), and an auxiliary processor 123 (eg, a graphics processing unit, an image signal processor) that can be operated independently or together. , A sensor hub processor, or a communication processor). Additionally or alternatively, the coprocessor 123 may be set to use less power than the main processor 121 or to be specialized for a designated function. The secondary processor 123 may be implemented separately from the main processor 121 or as a part thereof.

The coprocessor 123 is, for example, on behalf of the main processor 121 while the main processor 121 is in an inactive (eg, sleep) state, or the main processor 121 is active (eg, an application is executed). ) While in the state, together with the main processor 121, at least one of the components of the electronic device 101 (for example, the display device 160, the sensor module 176, or the communication module 190) It is possible to control at least some of the functions or states related to. According to an embodiment, the coprocessor 123 (eg, an image signal processor or a communication processor) may be implemented as part of another functionally related component (eg, the camera module 180 or the communication module 190). have.

The memory 130 may store various data used by at least one component of the electronic device 101 (eg, the processor 120 or the sensor module 176). The data may include, for example, input data or output data for software (eg, the program 140) and commands related thereto. The memory 130 may include a volatile memory 132 or a nonvolatile memory 134.

The program 140 may be stored as software in the memory 130, and may include, for example, an operating system 142, middleware 144, or an application 146.

The input device 150 may receive a command or data to be used for a component of the electronic device 101 (eg, the processor 120) from an outside (eg, a user) of the electronic device 101. The input device 150 may include, for example, a microphone, a mouse, a keyboard, or a digital pen (eg, a stylus pen).

The sound output device 155 may output an sound signal to the outside of the electronic device 101. The sound output device 155 may include, for example, a speaker or a receiver. The speaker can be used for general purposes such as multimedia playback or recording playback, and the receiver can be used to receive incoming calls. According to an embodiment, the receiver may be implemented separately from or as a part of the speaker.

The display device 160 may visually provide information to the outside of the electronic device 101 (eg, a user). The display device 160 may include, for example, a display, a hologram device, or a projector and a control circuit for controlling the device. According to an embodiment, the display device 160 may include a touch circuitry set to sense a touch, or a sensor circuit (eg, a pressure sensor) set to measure the strength of a force generated by the touch. have.

The audio module 170 may convert sound into an electric signal or, conversely, convert an electric signal into sound. According to an embodiment, the audio module 170 obtains sound through the input device 150, the sound output device 155, or an external electronic device (for example, an external electronic device directly or wirelessly connected to the electronic device 101). Sound may be output through the electronic device 102) (for example, a speaker or headphones).

The sensor module 176 detects an operating state (eg, power or temperature) of the electronic device 101, or an external environmental state (eg, a user state), and generates an electrical signal or data value corresponding to the detected state. can do. According to an embodiment, the sensor module 176 is, for example, a gesture sensor, a gyro sensor, an atmospheric pressure sensor, a magnetic sensor, an acceleration sensor, a grip sensor, a proximity sensor, a color sensor, an infrared (IR) sensor, a biometric sensor, It may include a temperature sensor, a humidity sensor, or an illuminance sensor.

The interface 177 may support one or more specified protocols that may be used to connect the electronic device 101 directly or wirelessly to an external electronic device (eg, the electronic device 102). According to an embodiment, the interface 177 may include, for example, a high definition multimedia interface (HDMI), a universal serial bus (USB) interface, an SD card interface, or an audio interface.

The connection terminal 178 may include a connector through which the electronic device 101 can be physically connected to an external electronic device (eg, the electronic device 102 ). According to an embodiment, the connection terminal 178 may include, for example, an HDMI connector, a USB connector, an SD card connector, or an audio connector (eg, a headphone connector).

The haptic module 179 may convert an electrical signal into a mechanical stimulus (eg, vibration or movement) or an electrical stimulus that a user can perceive through a tactile or motor sense. According to an embodiment, the haptic module 179 may include, for example, a motor, a piezoelectric element, or an electrical stimulation device.

The camera module 180 may capture a still image and a video. According to an embodiment, the camera module 180 may include one or more lenses, image sensors, image signal processors, or flashes.

The power management module 188 may manage power supplied to the electronic device 101. According to an embodiment, the power management module 188 may be implemented as, for example, at least a part of a power management integrated circuit (PMIC).

The battery 189 may supply power to at least one component of the electronic device 101. According to an embodiment, the battery 189 may include, for example, a non-rechargeable primary cell, a rechargeable secondary cell, or a fuel cell.

The communication module 190 is a direct (eg, wired) communication channel or a wireless communication channel between the electronic device 101 and an external electronic device (eg, electronic device 102, electronic device 104, or server 108). It is possible to support establishment and communication through the established communication channel. The communication module 190 operates independently of the processor 120 (eg, an application processor), and may include one or more communication processors that support direct (eg, wired) communication or wireless communication. According to an embodiment, the communication module 190 is a wireless communication module 192 (eg, a cellular communication module, a short-range wireless communication module, or a global navigation satellite system (GNSS) communication module) or a wired communication module 194 (eg : A LAN (local area network) communication module, or a power line communication module) may be included. Among these communication modules, a corresponding communication module is a first network 198 (for example, a short-range communication network such as Bluetooth, WiFi direct or IrDA (infrared data association)) or a second network 199 (for example, a cellular network, the Internet, or It is possible to communicate with an external electronic device (eg, electronic device 102, electronic device 104, or server 108) through a computer network (eg, a telecommunication network such as a LAN or WAN). These various types of communication modules may be integrated into one component (eg, a single chip), or may be implemented as a plurality of separate components (eg, multiple chips). The wireless communication module 192 uses subscriber information (e.g., International Mobile Subscriber Identifier (IMSI)) stored in the subscriber identification module 196 in a communication network such as the first network 198 or the second network 199. The electronic device 101 can be checked and authenticated.

The antenna module 197 may transmit a signal or power to the outside (eg, an external electronic device) or receive from the outside. According to an embodiment, the antenna module may include one antenna including a conductor formed on a substrate (eg, a PCB) or a radiator formed of a conductive pattern. According to an embodiment, the antenna module 197 may include a plurality of antennas. In this case, at least one antenna suitable for a communication method used in a communication network such as the first network 198 or the second network 199 is, for example, provided by the communication module 190 from the plurality of antennas. Can be chosen. Signal or power may be transmitted or received between the communication module 190 and an external electronic device through the at least one selected antenna. According to some embodiments, other components (eg, RFIC) other than the radiator may be additionally formed as part of the antenna module 197.

At least some of the components are connected to each other through a communication method (e.g., a bus, general purpose input and output (GPIO), serial peripheral interface (SPI), or mobile industry processor interface (MIPI))) between peripheral devices and signals ( E.g. commands or data) can be exchanged with each other.

According to an embodiment, commands or data may be transmitted or received between the electronic device 101 and the external electronic device 104 through the server 108 connected to the second network 199. Each of the electronic devices 102 and 104 may be a device of the same or different type as the electronic device 101. According to an embodiment, all or part of the operations executed by the electronic device 101 may be executed by one or more of the external electronic devices 102, 104, or 108. For example, when the electronic device 101 needs to perform a function or service automatically or in response to a request from a user or another device, the electronic device 101 does not execute the function or service by itself. In addition or in addition, one or more external electronic devices may be requested to perform the function or at least part of the service. One or more external electronic devices receiving the request may execute at least a part of the requested function or service, or an additional function or service related to the request, and transmit the execution result to the electronic device 101. The electronic device 101 may process the result as it is or additionally and provide it as at least a part of a response to the request. To this end, for example, cloud computing, distributed computing, or client-server computing technology may be used.

2 is a block diagram 200 illustrating a camera module 180 according to various embodiments. Referring to FIG. 2, the camera module 180 is a lens assembly 210, a flash 220, an image sensor 230, an image stabilizer 240, a memory 250 (eg, a buffer memory), or an image signal processor. It may include 260. The lens assembly 210 may collect light emitted from a subject to be imaged. The lens assembly 210 may include one or more lenses. According to an embodiment, the camera module 180 may include a plurality of lens assemblies 210. In this case, the camera module 180 may form, for example, a dual camera, a 360 degree camera, or a spherical camera. Some of the plurality of lens assemblies 210 have the same lens properties (eg, angle of view, focal length, auto focus, f number, or optical zoom), or at least one lens assembly may be a different lens assembly It may have one or more lens properties different from the lens properties of. The lens assembly 210 may include, for example, a wide-angle lens or a telephoto lens.

The flash 220 may emit light used to enhance light emitted or reflected from a subject. According to an embodiment, the flash 220 may include one or more light emitting diodes (eg, red-green-blue (RGB) LED, white LED, infrared LED, or ultraviolet LED), or a xenon lamp. The image sensor 230 may acquire an image corresponding to the subject by converting light emitted or reflected from the subject and transmitted through the lens assembly 210 into an electrical signal. According to an embodiment, the image sensor 230 is, for example, one image sensor selected from image sensors having different properties, such as an RGB sensor, a black and white (BW) sensor, an IR sensor, or a UV sensor. It may include a plurality of image sensors having attributes, or a plurality of image sensors having different attributes. Each image sensor included in the image sensor 230 may be implemented using, for example, a charged coupled device (CCD) sensor or a complementary metal oxide semiconductor (CMOS) sensor.

The image stabilizer 240 may move at least one lens or image sensor 230 included in the lens assembly 210 in a specific direction in response to the movement of the camera module 180 or the electronic device 101 including the same. The operating characteristics of the image sensor 230 may be controlled (eg, read-out timing, etc.) may be controlled. This makes it possible to compensate at least some of the negative effects of the movement on the image being photographed. According to an embodiment, the image stabilizer 240 is, according to an embodiment, the image stabilizer 240 is a gyro sensor (not shown) or an acceleration sensor (not shown) disposed inside or outside the camera module 180 Such movement of the camera module 180 or the electronic device 101 may be detected by using. According to an embodiment, the image stabilizer 240 may be implemented as, for example, an optical image stabilizer. The memory 250 may temporarily store at least a part of the image acquired through the image sensor 230 for the next image processing operation. For example, when image acquisition is delayed according to the shutter, or when a plurality of images are acquired at high speed, the acquired original image (eg, Bayer-patterned image or high resolution image) is stored in the memory 250 , A copy image corresponding thereto (eg, a low resolution image) may be previewed through the display device 160. Thereafter, when the specified condition is satisfied (eg, user input or system command), at least a part of the original image stored in the memory 250 may be acquired and processed by, for example, the image signal processor 260. According to an embodiment, the memory 250 may be configured as at least a part of the memory 130 or as a separate memory operated independently therefrom.

The image signal processor 260 may perform one or more image processing on an image acquired through the image sensor 230 or an image stored in the memory 250. The one or more image processes may be, for example, depth map generation, 3D modeling, panorama generation, feature point extraction, image synthesis, or image compensation (e.g. noise reduction, resolution adjustment, brightness adjustment, blurring ( blurring), sharpening, or softening In addition or alternatively, the image signal processor 260 includes at least one of the components included in the camera module 180 (eg, an image sensor). Control (eg, exposure time control, read-out timing control, etc.) for (230) The image processed by the image signal processor 260 is stored again in the memory 250 for further processing. Alternatively, it may be provided as an external component of the camera module 180 (for example, the memory 130, the display device 160, the electronic device 102, the electronic device 104, or the server 108). According to an example, the image signal processor 260 may be configured as at least a part of the processor 120, or may be configured as a separate processor that operates independently from the processor 120. The image signal processor 260 is the processor 120 When configured as a separate processor, at least one image processed by the image signal processor 260 may be displayed on the display device 160 as it is or after additional image processing is performed by the processor 120.

According to an embodiment, the electronic device 101 may include a plurality of camera modules 180 each having different attributes or functions. In this case, for example, at least one of the plurality of camera modules 180 may be a wide-angle camera, and at least the other may be a telephoto camera. Similarly, at least one of the plurality of camera modules 180 may be a front camera, and at least one of the camera modules 180 may be a rear camera.

3 is a diagram 300 illustrating an autofocus operation of an electronic device according to various embodiments of the present disclosure.

Referring to FIG. 3, the electronic device may include at least some components included in the electronic device 101 illustrated in FIG. 1. According to an embodiment, as illustrated, the electronic device may include a camera module 180, a processor 120, and a display device 160.

According to various embodiments, the camera module 180 may include a focus lens 310 and a driving unit 312.

The focus lens 310 may collect light emitted from a subject to be imaged, as described above with reference to FIG. 2. According to an embodiment, the focus lens 310 may adjust the focus of the lens assembly (eg, the lens assembly 210 of Fig. 2) by adjusting the position. For example, the focus lens 310 is on focus. -focus) area.

The driving unit 312 may drive the focus lens 310. According to an embodiment, the driving unit 312 may move the focus lens 310 to the on focus area so as to be in the on focus state. For example, the driving unit 312 may include a servo motor or an ultrasonic motor, and the driving unit 312 may be referred to as an auto focus motor or the like. However, this is only exemplary, and embodiments of the present invention are not limited thereto. As an example, the driving unit 312 may be configured with various types of auto focus motors capable of moving the focus lens 310 to the on focus area.

According to various embodiments, the processor 120 may include an image analysis unit 320, a defocus amount calculating unit 322, and an output control unit 320.

The processor 120 may generate an on-focus image by performing an auto focus function. The on-focus image may be an image focused on a subject. According to an embodiment, the auto focus function may include an operation of determining a search position and an operation of detecting an on focus area. The search position determination operation may be an operation of determining a start position of the on focus area detection operation. In addition, the operation of detecting the on focus area may be an operation of moving the focus lens 310 stepwise based on the search position and positioning it as the on focus area. The above-described search location determination operation and on focus area detection operation may be referred to by various names.

According to various embodiments, the processor 120 may perform a search location determination operation using various known techniques. According to an embodiment, the processor 120 may determine a search position based on the amount of defocus of the focus lens 310. The amount of defocus may be a value indicating a degree to which the focus lens 310 deviates from the on-focus area. For example, the image analysis unit 320 of the processor 120 calculates a focus signal value through frequency analysis of at least a portion of the first image and at least a portion of the second image having different focuses, and the processor 120 The defocus amount calculating unit 322 of may calculate the defocus amount based on the focus signal value. The focus signal value may be related to an amount of blur between the first image (or part of the first image) and the second image (or part of the second image). However, this is only exemplary, and embodiments of the present invention are not limited thereto. For example, the processor 120 may use a contrast between a first image and a second image, a phase difference between a first image and a second image, etc. as a focus signal value.

According to an embodiment, when the amount of defocus for the focus lens 310 is calculated, the processor 120 may predict an approximate position of the on-focus area based on the amount of defocus, and based on this, the focus lens 310 ) Movement direction and amount of movement can be determined. For example, when the focus lens 310 is out of the on-focus area by a reference range or more, the processor 120 may move the current position of the focus lens 310 to the search position by a first distance in the focus area direction. You can decide. As another example, when the focus lens 310 does not deviate from the reference range from the on focus area, the processor 120 may be spaced apart from the current position of the focus lens 310 by a second distance shorter than the first distance in the focus area direction. The location can be determined as the search location. In the present embodiment, it has been described that the moving direction and the position of the focus lens 310 are changed based on the amount of defocus, but this is only exemplary, and the embodiment of the present invention is not limited thereto. As an example, the processor 120 may also adjust the moving speed of the focus lens 310 based on the amount of defocus. For example, when the focus lens 310 is out of the on-focus area by more than a reference range, the processor 120 may move the focus lens 310 to the search position at the first speed. As another example, when the focus lens 310 does not deviate from the reference range from the on focus area, the processor 120 may move the focus lens 310 to the search position at a second speed slower than the first speed.

According to various embodiments, the processor 120 may limit the output of the second image while determining the search position. According to an embodiment, while determining the search position, the output control unit 324 of the processor 120 displays a first image obtained while the focus lens 310 is positioned at the first position on the display device 160. It can be processed to be output. For example, the output control unit 324 may output the first image instead of the second image even when the focus lens 310 at the first position moves to a second position in the opposite direction away from the on focus area. have. As a result, it is possible to prevent an image whose magnification changes due to a position change of the focus lens 310 from being output, thereby removing a wobbling phenomenon in which an image output to the display device 160 is shaken.

According to various embodiments of the present disclosure, when the above-described search position determining operation is completed, the processor 120 may detect the on-focus area based on the determined search position. According to an embodiment, the processor 120 may determine whether the focus lens 310 is close to the on focus area while moving the focus lens 310 at the second position in stages. For example, the processor 120 analyzes a focus signal value (eg, a contrast value) for an image acquired at a position where the focus lens 310 is moved, and when the maximum focus signal value is measured, the focus is close to the on-focus area. It can be judged that it did.

According to various embodiments of the present disclosure, when the on-focus area detection operation is performed, the processor 120 may output an image obtained in the search location determination operation. According to an embodiment, the output control unit 324 of the processor 120 displays the second image acquired at the second position while the focus lens 310 moves from the second position to the third position, which is the search start position. It can be processed to be output through (160). Accordingly, as will be described later with reference to FIGS. 9, 10A to 10C, and 11, it is possible to reduce a change in magnification of an image experienced by a user.

In the above-described embodiment, a configuration in which the auto focus function is performed by the processor 120 separated from the camera module 180 has been described. However, this is only exemplary, and embodiments of the present invention are not limited thereto. As an example, the auto focus function of the electronic device may be performed by a processor included in the camera module 180 (eg, the image signal processor 260 of FIG. 2 ).

An electronic device according to various embodiments of the present disclosure includes a camera module including a focus lens, a display device, and a processor, wherein the processor controls the camera module to acquire a first image at a first position of the focus lens, and Controls the display device to output a first image, controls the camera module to acquire a second image at a second position of the focus lens while the first image is output, and controls the first image and the first image 2 Based on the image, a defocus amount for the focus lens at the second position may be calculated, and the on-focus area may be detected based on the calculated defocus amount.

According to various embodiments of the present disclosure, the processor may control the display device to limit the output of the second image until the amount of defocus is calculated.

According to various embodiments, the processor controls the camera module to acquire a third image at a third position of the focus lens in response to the calculation of the defocus amount, and converts the first image to the third image. The display device can be controlled to update to.

According to various embodiments of the present disclosure, the processor may control the display device to output the second image before being updated to the third image.

According to various embodiments, the processor outputs the second image before being updated to the third image when the second position is in a first direction closer to the on focus area based on the first position. The display device can be controlled so as to be performed.

According to various embodiments of the present disclosure, when the focus lens moves more than a reference distance based on the second position in the first direction, the processor displays the display to output the second image before being updated to the third image. You can control the device.

According to various embodiments of the present disclosure, when the focus lens moves less than a reference distance based on the second position in the first direction, the processor is configured to maintain the output of the first image before being updated to the third image. The display device can be controlled.

According to various embodiments of the present disclosure, when the second position is in a second direction away from the on-focus area based on the first position, the processor may output the first image before being updated to the third image. The display device can be controlled to hold.

According to various embodiments of the present disclosure, the processor may control to detect the on focus area based on the contrast of the third image.

According to various embodiments of the present disclosure, the processor may control to calculate the amount of defocus based on a blur between the first image and the second image.

4 is a flowchart 400 for providing an auto focus function in an electronic device according to various embodiments of the present disclosure. In the following embodiments, each of the operations may be sequentially performed, but not necessarily sequentially. For example, the order of each operation may be changed, and at least two operations may be performed in parallel.

Referring to FIG. 4, according to various embodiments, the electronic device 300 (eg, the processor 120 of FIG. 3) acquires a first image for calculating a defocus amount, and obtains a first image. The image may be output to the display device 160. The first image may be an image obtained while the focus lens (eg, the focus lens 310 of FIG. 3) is positioned at the first position. According to an embodiment, the processor 120 may control a camera module (eg, the camera module 180 of FIG. 3) so that the first image is acquired.

According to various embodiments of the present disclosure, in operation 420, the electronic device 300 (eg, the processor 120 of FIG. 3) may acquire a second image for calculating a defocus amount. The second image may be an image obtained while the focus lens 310 positioned at the first position is moved to the second position. For example, the processor 120 may control the camera module to obtain a second image in which the image magnification is increased or decreased compared to the first image due to a position change of the focus lens 310. According to an embodiment, the processor 120 may acquire the second image while the first image is output to the display device 106. For example, the processor 120 may limit the output of the acquired second image, as described later through FIG. 5B.

According to various embodiments, in operation 430, the electronic device 300 (eg, the processor 120 of FIG. 3) calculates a defocus amount for the focus lens 310 based on the first image and the second image. I can. As described above with reference to FIG. 3, the amount of defocus may be a value indicating a degree to which the current focusing lens 310 deviates from the on-focus area. According to an embodiment, the processor 120 may calculate the amount of defocus while the first image is being output. For example, the processor 120 may process the first image to be output to the display device 106 instead of the second image until the amount of defocus for the focus lens 310 is calculated.

According to various embodiments of the present disclosure, in operation 440, the electronic device 300 (eg, the processor 120 of FIG. 3) may perform an operation of detecting an on-focus area based on the calculated amount of defocus. For example, the processor 120 may determine a position at which the detection operation of the on-focus area starts based on the amount of defocus. Also, the processor 120 may move the focus lens 310 to the on focus area in stages based on the determined start position.

5A and 5B are exemplary views 500 and 550 for explaining a comparison between an autofocus function of a general electronic device and an autofocus function of an electronic device according to various embodiments of the present disclosure.

Referring to FIG. 5A, a general electronic device 102 may provide an auto focus function for focusing on a subject by moving a lens included in the camera module back and forth. The electronic device 102 displays the image 502 acquired through the camera module (eg, the camera module 180 of FIG. 3) while the auto focus function is being executed through the display device 160 in the form of a preview image or a live view. It can be output to (504). For example, as shown, when the focus lens 310 moves to the second lens position while outputting the first image acquired at the first lens position, the electronic device 102 The screen may be updated using the acquired second image. At this time, as shown, when the focus lens 310 moves to a second lens position opposite to the first lens position and then moves to a third lens position opposite to the second lens position, the electronic device After 102 outputs a second image whose screen magnification is reduced compared to the first image, a wobbling phenomenon in which the output image is shaken may occur as a third image whose screen magnification is increased compared to the second image is output.

Referring to FIG. 5B, the electronic device 102 according to various embodiments of the present disclosure may prevent a wobbling phenomenon by controlling an image output while an auto focus function is performed. Specifically, the electronic device 102 may limit the output of the second image and maintain the output of the first image while at least calculating the amount of defocus. For example, when the focus lens 310 moves to a second lens position opposite to the first lens position and then moves to a third lens position opposite to the second lens position, the electronic device 102 After the first image is output, the third image is output 550 so that the user can recognize that the image magnification linearly increases or decreases.

6 is a flowchart 600 for calculating a defocus amount in an electronic device according to various embodiments of the present disclosure. The operations of FIG. 6 described below may represent various embodiments of the operations 410 and 430 of FIG. 4. In addition, in the following embodiments, each of the operations may be sequentially performed, but not necessarily sequentially. For example, the order of each operation may be changed, and at least two operations may be performed in parallel.

Referring to FIG. 6, according to various embodiments, the electronic device 300 (for example, the processor 120 of FIG. 3) may acquire and output a first image based on a first lens position in operation 610. . According to an embodiment, the processor 120 may acquire a first image of the subject by sensing light of a subject incident through the focus lens (eg, the focus lens 310 of FIG. 3) at the first position. .

According to various embodiments, the electronic device 300 (for example, the processor 120 of FIG. 3) may extract a partial area of the acquired first image in operation 620. According to an embodiment, a partial area of the first image may be a portion used for focus detection. According to an embodiment, the processor 120 may use a central portion of the first image for focus detection. However, this is only exemplary, and embodiments of the present invention are not limited thereto. As an example, the processor 120 may use various portions of the first image, such as a corner portion of the first image and an edge portion detected in the first image, for focus detection. According to an embodiment, the processor 120 converts the acquired first image or a partial area of the first image into or outside the electronic device 300 (for example, the electronic device 102, 104, or the server 108). You can also save it.

According to various embodiments, the electronic device 300 (eg, the processor 120 of FIG. 3) may change the focus lens 310 at the first position to the second position in operation 630. The second position to which the focus lens 310 moves may be determined by a predefined algorithm.

According to various embodiments of the present disclosure, in operation 640, the electronic device 300 (eg, the processor 120 of FIG. 3) may acquire the second image based on the position of the second lens. According to an embodiment, the processor 120 may acquire a second image of the subject by sensing light of an incident object through the focus lens 310 whose position is changed from the first position to the second position.

According to various embodiments of the present disclosure, in operation 650, the electronic device 300 (eg, the processor 120 of FIG. 3) may limit the output of the second image and maintain the output of the first image. According to an embodiment, as the moving direction of the focus lens 310 is changed, the processor 120 may prevent output of a second image with an increased or decreased image magnification compared to the first image.

According to various embodiments, the electronic device 300 (eg, the processor 120 of FIG. 3) may extract a partial area of the acquired second image in operation 660. According to an embodiment, a partial area of the second image may be a portion used for focus detection. According to an embodiment, the processor 120 may use the central portion of the second image for focus detection. However, this is only exemplary, and embodiments of the present invention are not limited thereto. As an example, the processor 120 may use various portions of the second image, such as a corner portion of the second image and an edge portion detected in the second image, for focus detection. According to an embodiment, the processor 120 may convert the acquired second image or a partial area of the second image into or out of the electronic device 300 (for example, the electronic device 102, 104, or the server 108). You can also save it.

According to various embodiments of the present disclosure, in operation 670, the electronic device 300 (eg, the processor 120 of FIG. 3) may measure a focus signal value based on the extracted regions. According to an embodiment, the processor 120 performs frequency analysis on the first image (or a partial region of the first image) and the second image (or a partial region of the second image), as described above with reference to FIG. 3. Through this, focus signal values such as blur, contrast, and phase difference between images may be measured.

According to various embodiments, the electronic device 300 (eg, the processor 120 of FIG. 3) may calculate a defocus amount for the focus lens 310 based on the calculated focus signal value in operation 680. . According to an embodiment, the processor 120 may store a reference defocus amount in which a defocus amount corresponding to various focus signal values is predefined. In this case, the processor 120 may calculate a defocus amount for the current focus lens 310 by comparing the calculated focus signal value with a reference defocus amount. According to various embodiments of the present disclosure, as described above with reference to FIG. 3, the processor 120 may determine a search position based on the calculated amount of defocus. According to an embodiment, when the focus lens 310 is out of the on-focus area by a reference range or more, the processor 120 searches for a position spaced apart from the current position of the focus lens 310 by a first distance in the focus area direction. Can be determined by location. According to another embodiment, when the focus lens 310 does not deviate from the reference range from the on-focus area, the processor 120 may provide a second distance shorter than the first distance in the focus area direction from the current position of the focus lens 310. A location that is spaced apart can be determined as a search location.

7 is a flowchart 700 for detecting an on-focus area in an electronic device according to various embodiments of the present disclosure. In addition, FIG. 8 is an exemplary diagram for describing an operation of detecting an on-focus area in an electronic device according to various embodiments of the present disclosure. The operations of FIG. 7 described below may represent various embodiments of operation 440 of FIG. 4. In addition, in the following embodiments, each of the operations may be sequentially performed, but not necessarily sequentially. For example, the order of each operation may be changed, and at least two operations may be performed in parallel.

Referring to FIG. 7, according to various embodiments, the electronic device 300 (eg, the processor 120 of FIG. 3) may maintain an output of the first image in operation 710. The first image may be an image obtained from a previous position of the focus lens (eg, the focus lens 310 of FIG. 3 ). According to an embodiment, even if the second image is acquired based on the second lens position, the processor 120 may output the first image acquired at the previous position of the focus lens 310 instead of the second image.

According to various embodiments of the present disclosure, in operation 720, the electronic device 300 (eg, the processor 120 of FIG. 3) may move the focus lens 310 based on the search position.

According to various embodiments of the present disclosure, in operation 730, the electronic device 300 (for example, the processor 120 of FIG. 3) may perform a search operation using the focus lens 310 moved to the search position. According to an embodiment, the processor 120 may measure a focus signal value (eg, a contrast value) for an image acquired through the focus lens 310 moved to the search position. Also, the processor 120 may acquire an image while gradually moving the focus lens 310 to the on-focus area, and measure a focus signal value for the acquired image.

According to various embodiments of the present disclosure, in operation 740, the electronic device 300 (eg, the processor 120 of FIG. 3) may determine whether the focus lens 310 is close to the on focus area. According to an embodiment, when a focus signal value for an image acquired at a position where the focus lens 310 is moved is measured as a maximum focus signal value, the processor 120 may determine that the focus lens 310 is close to the on focus area. For example, the processor 120 may provide a focus signal value for a current position of the focus lens 310 (eg, a first focus signal value) with respect to a focus signal value for a previous position of the focus lens 310 (eg, a first focus signal value). The ratio of the second focus signal value (eg, the second focus signal value / the first focus signal value) may be calculated. In addition, the processor 120 may determine that the ratio of the focus signal value increases and decreases according to the movement of the focus lens 310 or that the focus signal value approaches the on-focus area at a time point when the ratio of the focus signal value decreases and increases.

According to various embodiments, when it is determined that the focus lens 310 is not close to the on-focus area, that is, when the ratio of the focus signal value according to the movement of the focus lens 310 continuously increases or decreases, the electronic The device 300 (eg, the processor 120 of FIG. 3) may repeatedly perform a search operation. For example, as mentioned in operation 730, the processor 120 may acquire an image while gradually moving the focus lens 310 to the on focus area, and measure a focus signal value for the acquired image.

According to various embodiments, when it is determined that the focus lens 310 is close to the on-focus area, that is, when the ratio of the focus signal value according to the movement of the focus lens 310 increases and then decreases or decreases and then increases, The electronic device 300 (eg, the processor 120 of FIG. 3) may generate an on-focus image in operation 750. According to an embodiment, the on-focus image may be an image in which a subject is focused through a focus lens 310 located in the on-focus area. For example, the processor 120 may detect an on-focus position and move the focus lens 310 to the detected on-focus position in order to generate an on-focus image. For example, as illustrated in FIG. 8, the processor 120 may detect the on-focus position using 3-point interpolation. Specifically, the processor 120 may calculate a focus signal value for each position while moving the focus lens 310 step by step. For example, the processor 120 may calculate a focus signal value while moving from the first position to the seventh position. Further, the processor 120 may determine that the focus lens 310 is located near the focus area from the point where the focus lens 310 moves from the sixth position to the seventh position. In this case, the processor 120 sets the point P where the line L1 connecting the focus signal values at positions 5 and 6 and the tangent line L2 of the focus signal value at the 7 positions meet as the on focus point. After determining, it is possible to finally move the focus lens 310 to the point P. However, this is only exemplary, and embodiments of the present invention are not limited thereto. As an example, the processor 120 may determine the on-focus point based on various known methods. According to an embodiment, the processor 120 may output the generated on-focus image as a preview image or a live view. However, this is only exemplary, and embodiments of the present invention are not limited thereto. For example, the processor 120 may store the on-focus image inside or outside the electronic device 300 (eg, the electronic device 102, 104, or the server 108).

9 is a flowchart 900 for moving a focus lens based on a search position in an electronic device according to various embodiments of the present disclosure. The operations of FIG. 9 described below may represent various embodiments of operation 720 of FIG. 7. In addition, in the following embodiments, each of the operations may be sequentially performed, but not necessarily sequentially. For example, the order of each operation may be changed, and at least two operations may be performed in parallel.

Referring to FIG. 9, in operation 910 of the electronic device 300 (eg, the processor 120 of FIG. 3 ), according to various embodiments, a second lens position exists in a first direction based on a first lens position. Whether or not the second lens position exists in the second direction based on the first lens position may be determined. For example, the first lens position may be an acquisition position of the first image for calculating the amount of defocus, and the second lens position may be an acquisition position of the second image for calculating the amount of defocus. In addition, the first direction may be a direction closer to the on focus area based on the first lens position, and the second direction may be a direction away from the on focus area based on the first lens position.

According to various embodiments, when it is determined that the second lens position is in the first direction, the electronic device 300 (for example, the processor 120 of FIG. 3) may perform an operation 920 on the previously acquired second image. The screen can be updated based on it. According to an embodiment, the processor 120 may process the second image to be displayed on the screen until the focus lens (eg, the focus lens 310 of FIG. 3) moves to the search position. For example, as described later through FIGS. 10A to 10C, the processor 120 temporarily outputs the second image after outputting the first image, thereby reducing the magnification change of the image experienced by the user when outputting the third image. I can.

According to various embodiments, when it is determined that the second lens position is in the second direction, the electronic device 300 (eg, the processor 120 of FIG. 3) may maintain the output of the first image in operation 930. have. According to an embodiment, the processor 120 may maintain the output of the first image until the focus lens 310 moves to the search position.

10A to 10C are exemplary views illustrating an operation of moving a focus lens based on a search position in an electronic device according to various embodiments of the present disclosure.

Referring to FIG. 10A, as described above, the electronic device 300 according to various embodiments of the present disclosure includes a first image acquired based on a first lens position and a second image 1002 acquired based on a second lens position. The amount of defocus can be calculated based on. Also, while the amount of defocus is calculated, the electronic device 300 may prevent wobbling by limiting the output of the second image and outputting only the first image (1004). Also, the electronic device 300 may perform an operation of detecting a focus area by moving the focus lens 310 to the third lens position based on the amount of defocus.

According to various embodiments of the present disclosure, the electronic device 300 may control to output a second image while moving the focus lens 310 to the third position. As shown in FIG. 10A, images whose image magnification linearly increases according to the movement of the focus lens 310 may be obtained, but the electronic device 300 according to various embodiments of the present disclosure prevents the wobbling phenomenon. In order to do so, the user can output 1002 the second image while the focus lens 310 moves to the third lens position (or until the third image is output) after outputting the first image instead of the second image. It is possible to reduce the change in magnification for the perceived image.

For example, as illustrated in FIG. 10B, when the output of the first image 1011 is maintained until the third image 1013 is output, a change in magnification of the image experienced by the user may increase. On the other hand, as shown in FIG. 10C, when the second image 1012 is temporarily output before the third image 1013 is output, the magnification change for the image experienced by the user compared to the situation shown in FIG. 10B Can reduce.

11 is a flowchart 1100 for updating a screen based on a second image in an electronic device according to various embodiments of the present disclosure. The operations of FIG. 11 described below may represent various embodiments of operation 920 of FIG. 9. In addition, in the following embodiments, each of the operations may be sequentially performed, but not necessarily sequentially. For example, the order of each operation may be changed, and at least two operations may be performed in parallel.

Referring to FIG. 11, in operation 1110 of the electronic device 300 (eg, the processor 120 of FIG. 3) according to various embodiments, a focus lens (eg, the focus lens 310 of FIG. 3) is It may be determined whether the search operation is performed by being spaced apart by a predefined reference distance based on the lens position. The reference distance may be a value for determining a situation in which a user can experience a change in magnification of an image.

According to various embodiments, when a search operation is performed in a state spaced apart by a reference distance, that is, in a situation in which a user can experience a change in magnification of an image, the electronic device 300 (eg, the processor of FIG. 3 ). In operation 1120 (120), the screen may be updated based on the second image. According to an embodiment, the processor 120 may process the second image to be displayed on the screen until the focus lens 310 moves to the search position.

According to various embodiments, when a search operation is performed without being separated by a reference distance, that is, when a user cannot experience a change in magnification of an image, the electronic device 300 (eg, in FIG. 3 ). The processor 120 may maintain the output of the first image in operation 1130. According to an embodiment, the processor 120 may maintain the output of the first image until the focus lens 310 moves to the search position.

According to various embodiments of the present disclosure, a method of operating an electronic device may include an operation of acquiring a first image at a first position of a focus lens, an operation of outputting the first image through a display device, and while the first image is output, An operation of acquiring a second image at a second position of the focus lens, an operation of calculating a defocus amount for the focus lens at the second position based on the first image and the second image, and the calculated D It may include an operation of detecting the on-focus area based on the amount of focus.

According to various embodiments of the present disclosure, calculating the amount of defocus may include limiting the output of the second image while the first image is being output.

According to various embodiments, detecting the on-focus area may include acquiring a third image at a third position of the focus lens, and updating the first image to the third image. .

According to various embodiments of the present disclosure, the detecting of the on-focus area may include outputting the second image before being updated to the third image.

According to various embodiments of the present disclosure, when the second position is in a first direction approaching the on focus area based on the first position, the detecting of the on focus area may be performed before being updated to the third image. It may include an operation of outputting the second image.

According to various embodiments of the present disclosure, when the focus lens moves by a reference distance or more based on the second position in the first direction, the detection of the on-focus area is performed by the second image before being updated to the third image. It may include an operation of outputting an image.

According to various embodiments of the present disclosure, when the focus lens moves less than a reference distance based on the second position in the first direction, the detecting of the on-focus area is performed before being updated to the third image. It may include the operation of maintaining the image output.

According to various embodiments of the present disclosure, when the second position is in a second direction away from the on focus area based on the first position, the detecting of the on focus area may be performed before being updated to the third image. It may include an operation of maintaining the output of the first image.

According to various embodiments of the present disclosure, detecting the on-focus area may include calculating a contrast of the third image.

According to various embodiments of the present disclosure, calculating the amount of defocus may include calculating a blur between the first image and the second image.

According to various embodiments, the computer-readable recording medium includes an operation of acquiring a first image at a first position of a focus lens, an operation of outputting the first image through a display device, and an operation of outputting the first image. Acquiring a second image at a second position of a focus lens, calculating a defocus amount for the focus lens at the second position based on the first image and the second image, and the calculated defocus A program for executing an operation of detecting the on-focus area based on the amount may be stored.

Electronic devices according to various embodiments disclosed in this document may be devices of various types. The electronic device may include, for example, a portable communication device (eg, a smart phone), a computer device, a portable multimedia device, a portable medical device, a camera, a wearable device, or a home appliance. The electronic device according to the exemplary embodiment of the present document is not limited to the above-described devices.

Various embodiments of the present document and terms used therein are not intended to limit the technical features described in this document to specific embodiments, and should be understood to include various modifications, equivalents, or substitutes of the corresponding embodiments. In connection with the description of the drawings, similar reference numerals may be used for similar or related components. The singular form of a noun corresponding to an item may include one or a plurality of the items unless clearly indicated otherwise in a related context. In this document, "A or B", "at least one of A and B", "at least one of A or B, "A, B or C," "at least one of A, B and C, and "A, B Each of the phrases such as ", or at least one of C" may include any one of the items listed together in the corresponding one of the phrases, or all possible combinations thereof. Terms such as "first", "second", or "first" or "second" may be used simply to distinguish the component from other corresponding components, and the components may be referred to in other aspects (eg, importance or Order) is not limited. Some (eg, first) component is referred to as “coupled” or “connected” to another (eg, second) component, with or without the terms “functionally” or “communicatively”. When mentioned, it means that any of the above components can be connected to the other components directly (eg by wire), wirelessly, or via a third component.

The term "module" used in this document may include a unit implemented in hardware, software, or firmware, and may be used interchangeably with terms such as logic, logic blocks, parts, or circuits. The module may be an integrally configured component or a minimum unit of the component or a part thereof that performs one or more functions. For example, according to an embodiment, the module may be implemented in the form of an application-specific integrated circuit (ASIC).

Various embodiments of the present document include one or more commands stored in a storage medium (eg, internal memory 136 or external memory 138) that can be read by a machine (eg, electronic device 101). It may be implemented as software (for example, the program 140) including them. For example, the processor (eg, the processor 120) of the device (eg, the electronic device 101) may call and execute at least one command among one or more commands stored from a storage medium. This makes it possible for the device to be operated to perform at least one function according to the at least one command invoked. The one or more instructions may include code generated by a compiler or code executable by an interpreter. A storage medium that can be read by a device may be provided in the form of a non-transitory storage medium. Here,'non-transient' only means that the storage medium is a tangible device and does not contain a signal (e.g., electromagnetic wave), and this term refers to the case where data is semi-permanently stored in the storage medium. It does not distinguish between temporary storage cases.

According to an embodiment, a method according to various embodiments disclosed in the present document may be provided by being included in a computer program product. Computer program products can be traded between sellers and buyers as commodities. The computer program product is distributed in the form of a device-readable storage medium (e.g. compact disc read only memory (CD-ROM)), or through an application store (e.g. Play Store ^TM ) or two user devices ( It can be distributed (e.g., downloaded or uploaded) directly between, e.g. smartphones). In the case of online distribution, at least a portion of the computer program product may be temporarily stored or temporarily generated in a storage medium that can be read by a device such as a server of a manufacturer, a server of an application store, or a memory of a relay server.

According to various embodiments, each component (eg, module or program) of the above-described components may include a singular number or a plurality of entities. According to various embodiments, one or more components or operations among the above-described corresponding components may be omitted, or one or more other components or operations may be added. Alternatively or additionally, a plurality of components (eg, a module or a program) may be integrated into one component. In this case, the integrated component may perform one or more functions of each component of the plurality of components in the same or similar to that performed by the corresponding component among the plurality of components prior to the integration. . According to various embodiments, operations performed by a module, program, or other component may be sequentially, parallel, repeatedly, or heuristically executed, or one or more of the operations may be executed in a different order or omitted. , Or one or more other actions may be added.

Claims (20)

In the electronic device,
A camera module including a focus lens;
Display device; And
Includes a processor, the processor,
Controlling the camera module to acquire a first image at a first position of the focus lens,
Controlling the display device to output the first image,
While the first image is being output, controlling the camera module to acquire a second image at a second position of the focus lens,
Calculating a defocus amount for the focus lens at the second position based on the first image and the second image,
An electronic device that controls to detect an on-focus area based on the calculated amount of defocus.
The method of claim 1,
The processor,
An electronic device that controls the display device to limit the output of the second image until the amount of defocus is calculated.
The method of claim 1,
The processor,
In response to the calculation of the amount of defocus, controlling the camera module to acquire a third image at a third position of the focus lens,
An electronic device that controls the display device to update the first image with the third image.
The method of claim 3,
The processor,
An electronic device that controls the display device to output the second image before being updated with the third image.
The method of claim 4,
The processor,
An electronic device configured to control the display device to output the second image before being updated to the third image when the second position is in a first direction closer to the on focus area based on the first position.
The method of claim 5,
The processor,
When the focus lens moves by a reference distance or more based on the second position in the first direction, the electronic device controls the display device to output the second image before being updated to the third image.
The method of claim 6,
The processor,
When the focus lens moves less than a reference distance based on the second position in the first direction, the electronic device controls the display device to maintain the output of the first image before being updated to the third image.
The method of claim 4,
The processor,
An electronic device that controls the display device to maintain the output of the first image before being updated to the third image when the second position is in a second direction away from the on focus area based on the first position .
The method of claim 3,
The processor,
The electronic device controls to detect the on-focus area based on the contrast of the third image.
The method of claim 1,
The processor,
An electronic device controlling to calculate the amount of defocus based on a blur between the first image and the second image.
In the method of operating an electronic device,
Acquiring a first image at a first position of the focus lens;
Outputting the first image through a display device;
Obtaining a second image at a second position of the focus lens while the first image is being output;
Calculating a defocus amount for the focus lens at the second position based on the first image and the second image; And,
And detecting an on-focus area based on the calculated amount of defocus.
The method of claim 11,
The operation of calculating the defocus amount,
And limiting the output of the second image while the first image is being output.
The method of claim 11,
The operation of detecting the on-focus area,
Acquiring a third image at a third position of the focus lens; And
And updating the first image to the third image.
The method of claim 13,
The operation of detecting the on-focus area,
The method further comprising outputting the second image before being updated with the third image.
The method of claim 14,
The operation of detecting the on-focus area,
And outputting the second image before being updated to the third image when the second position is in a first direction approaching an on focus area based on the first position.
The method of claim 15,
The operation of detecting the on-focus area,
And outputting the second image before being updated to the third image when the focus lens moves more than a reference distance based on the second position in the first direction.
The method of claim 16,
The operation of detecting the on-focus area,
And when the focus lens moves less than a reference distance based on the second position in the first direction, maintaining the output of the first image before being updated to the third image.
The method of claim 14,
The operation of detecting the on-focus area,
And maintaining the output of the first image before being updated to the third image when the second position is in a second direction away from the on focus area based on the first position.
The method of claim 13,
The operation of detecting the on-focus area,
And calculating the contrast of the third image.
The method of claim 11,
The operation of calculating the defocus amount,
And calculating a blur between the first image and the second image.

Images